Hello, I am quite new to whole electronics and I have been given an assignment in school to do a project with arduino. I selected DHT11 sensor because it was cheap and reliable as I read on the Internet. I have no trouble with getting readings from DHT11 to Arduino software alone or hooking up LCD and displaying something on it. Trouble comes in when I try to display DHT11 readings on the LCD and get readings to computer at the same time. I´m sure this has been done before but I could not find anything on the Internet. Maybe someone of you could try and help me out a little bit?

Seriously, you need to give us something more to go on than "Trouble comes in when I try to display DHT11 readings on the LCD and get readings to computer at the same time.". Something like what the trouble is would be extremely helpful.

Demonstrates the use a 16x2 LCD display. The LiquidCrystal library works with all LCD displays that are compatible with the Hitachi HD44780 driver. There are many of them out there, and you can usually tell them by the 16-pin interface.

This sketch prints "Hello World!" to the LCD and uses the scrollDisplayLeft() and scrollDisplayRight() methods to scroll the text.

//See for more information....//http://sheepdogguides.som/arduino/ar3ne1humDHT11.htm

//N.B. "bit" is used in the narrow, computer "1 or 0"// sense throughout.

//"DHT" from sensor's names: DHT11, DHT22.//DHT aka Aosong AM2302, and there's an AM2303 which//seems to be in the same family.

//Comments on this based on Aosong AM2302, aka DHT22, datasheet.//Believed to generally apply to DHT11 as well, except in the//case of the DHT11, I believe the second and fourth bytes are//always zero.

//***N.B.****//The code WORKS... the comments may not yet be EXACTLY right.//See the web-page cited above for latest news.

//That "module", according to the//nuelectronics site, and visual inspection simply provides for easy//connection of an Aosong DHT11 unit to the nuelectronics datalogging//shield. Only 3 wires are involved: Vcc, ground, and a single data//line. One of the DHT11's 4 pins goes nowhere.

//You should not need to change anything except the next line to use//the software with the sensor on a different line, or for a DHT22.

//Just "huffing" on the sensor from deeply filled lungs should show//a near instant rise in humidity

//#define dht_PIN 0 //no ; here. deprecate ADC0...//even though we are using it as a digital pin.//Other parts of code restrict us to using//ADC0-5, aka D14-19#define dht_dpin 14 //no ; here. Set equal to channel sensor is on,//where if dht_dpin is 14, sensor is on digital line 14, aka analog 0

/*After 80us low, the line should be taken high for 80us by the sensor. The low following that high is the start of the first bit of the forty to come. The routine "read_dht_dat()" expects to be called with the system already into this low.*/ delayMicroseconds(70);//now ready for data reception... pick up the 5 bytes coming from// the sensor for (i=0; i<5; i++) dht_dat[i] = read_dht_dat();

//Next: Make data line high again, as output from Arduino digitalWrite(dht_dpin,HIGH); //Was: PORTC |= _BV(dht_PIN);//N.B.: Using PORTC put restrictions on value of dht_pin

//Next see if data received consistent with checksum received byte dht_check_sum = dht_dat[0]+dht_dat[1]+dht_dat[2]+dht_dat[3];/*Condition in following "if" says "if fifth byte from sensor not the same as the sum of the first four..."*/ if(dht_dat[4]!= dht_check_sum) {bGlobalErr=3; } //Was: Serial.println("DHT11 checksum error");}; //end ReadDHT()

//Dataline will now stay high for 27 or 70 uS, depending on //whether a 0 or a 1 is being sent, respectively. delayMicroseconds(30); //AFTER pin is high, wait further period, to be //into the part of the timing diagram where a 0 or a 1 denotes //the datum being send. The "further period" was 30uS in the software //that this has been created from. I believe that a higher number //(45?) would be more appropriate.

... and they all work, but I would love to be able to use the last script but get the readings on the arduino software port monitor as well so I could have data readings saved all throught night.. I have never been programming or anything alike, but I do enjoy the wiring part and making something myself.. Thanks alot to everyone who want to help me.